Automatically strikethrough referenced issues/MRs that are closed or merged.

Summary

When referencing something in a MR, comment, or issue that is closed or becomes closed, it would be very nice if the item was formatted to strikethrough (~~#142~~) automatically.

Example

(Ceci n'est pas une reference.)

Benefits:

It looks like GitLab likes to use issue collections (such as #13559 (closed)) that reference other issues. I've noticed that people have to edit the collection issue with "DONE" whenever a referenced item is complete.

This would remove that extra minor step (which is probably easily forgotten).

This seems like a cool idea to do :)

As for my MR I'm updating it after the release cycle.

Added ~159098 label

Added feature proposal label

I'm closing this as a duplicate of https://gitlab.com/gitlab-org/gitlab-ce/issues/1369

Status changed to closed